The U.S. government performed documented human experiments on its own people during the Cold War without their knowledge or consent. NewsNation dives into the question: What were they doing in St. Louis? Watch Elizabeth Vargas Reports, Wednesday at 7p/6C. | NewsNation

Dr. William Haseltine says testing a Covid-19 vaccine on a healthy person is unethical and dangerous. "There are plenty of patients out there," he says, adding "it's uninformative because most of the people who [volunteer] are going to be young, and who really needs the vaccine are old people. Nobody in their right mind would give a live virus to an old, susceptible person... It's unethical. We have a good memory of the horrors of human experimentation starting in the 1940's and '50s ... do we r